Yet Mark Harmon was just voted America’s favorite television personality.

Harmon, who currently stars as Special Agent Leroy Jethro Gibbs on the CBS procedural “NCIS” — which last week pulled in an astounding 22 million viewers, its largest audience ever — outranks such superstars as Oprah Winfrey (No. 2), Conan O’Brien (No. 4) and Charlie Sheen (No. 5) in a Harris poll.

It’s a huge leap for the seemingly ageless Harmon, who ranked No. 8 last year — and wasn’t even on the list for the two decades before that.

“To trot out the classic quip, he represents who other men want to be and who women want to be with,” said Matt Mitovich, editor-at-large of TVLine.com. “Throughout so many of his roles, Mark has been an almost iconic representation of a salt-of-the-earth, upstanding guy.”

His breakthrough role playing serial killer Ted Bundy in a TV movie notwithstanding, Harmon has been a fixture on primetime dramas for well over two decades. He made headlines as Dr. Robert Caldwell on the 1980s smash “St. Elsewhere,” playing one of the first mainstream characters to contract AIDS.

Harmon left the show in 1986, the same year he beat out Tom Cruise, Harrison Ford, Bruce Willis and JFK Jr. for “Sexiest Man Alive.”

The profile, titled “Charmin’ Harmon,” opened inauspiciously: “OK, we know what you’re thinking: Where’d they get this guy?”

The magazine went on to describe the all-American appeal of Harmon, a former UCLA quarterback and the son of late Heisman Trophy winner Tom Harmon: “Dependable. Loyal. Romantic . . . the reincarnation of the strong, silent type.”

In 1987, Harmon married sitcom star Pam Dawber, of “Mork & Mindy” fame. They have two sons, Sean Thomas, 22, and Ty Christian, 18. His sister, Kristen, was married to 1950s teen idol Ricky Nelson, who was killed in a plane crash in 1986.

Harmon’s closest encounter with scandal was a 1987 custody battle for Kristen’s teenage son; Harmon charged that she was an unfit parent, but he later dropped the suit. His reputation was only burnished.

He also downplayed his role in saving the lives of two teenage boys who crashed their car into his and Dawber’s LA street in 1996. Using a 12-pound sledgehammer, Harmon smashed the car’s windows and dragged both boys to safety before the car blew up.

Ever taciturn and reticent, he’s avoided talking about it, though last year he told USA Today, “If the car blows up and kills me and the kids in the car, then you’d be doing this interview with my wife about how stupid it was.”

Harmon hit his all-American apotheosis in 2002 on “The West Wing,” playing an impossibly valiant yet doomed Secret Service agent.

“It proved him to be an actor people love to tune in for,” said TVLine’s Mitovich.

That led to his being cast on CBS’s military procedural “JAG” — a two-episode stint that led to the “NCIS” spin-off, now pulling in Super Bowl-level ratings.

“Times are tough in America,” Mitovich said. “And Harmon — largely because of his role on ‘NCIS’ — perhaps symbolizes a real American hero. When he gets a close-up, you can almost see the Stars and Stripes waving behind him.”